Mild Palladium‐Catalyzed Oxidative Direct ortho‐C?H Acylation of Anilides under Aqueous Conditions

Palladium‐catalyzed cross‐dehydrogenative coupling between anilides and aromatic aldehydes was achieved under aqueous conditions. A wide variety of the desired benzophenone derivatives was isolated in good to excellent yield. The reaction rate acceleration effect of acid and detergent has been demonstrated. Mechanistic insight has been obtained from quantum chemical calculations.     

High-power InAs/InAsSbP heterostructure leds for methane spectroscopy (λ ≈ 3.3 μm)

Two designs of light-emitting diodes (LEDs) based on InAsSbP/InAs/InAsSbP double hetero-structures grown by metal-organic vapor phase epitaxy on p− and n-InAs substrates have been studied. The current-voltage and electroluminescence characteristics of the LEDs are analyzed. It is shown that the LED design with a light-emitting crystal (chip) mounted with the epitaxial layer down on the LED case and emission extracted through the n-InAs substrate provides better heat removal. As a result, the spectral characteristics remain stable at increased injection currents and the quantum efficiency of radiative recombination is higher. The internal quantum efficiency of light-em itting structures with an emission wavelength λ = 3.3–3.4 μm is as high as 22.3%. The optical emission power of the LEDs is 140 μW at a current of 1 A in the quasi-continuous mode and reaches a value of 5.5 mW at a current of 9 A in the pulsed mode.     

Effect of genetic and nongenetic factors on chemical composition of individual milk samples from dromedary camels (Camelus dromedarius) under intensive management

The aims of the present study were to monitor the changes in gross chemical composition of individual dromedary camel milk over a 5-yr period, to provide reference values, and to determine the effect of genetic and nongenetic factors influencing camel milk composition under intensive management. A total of 1,528 lactating dromedary camels were included in the study. Animals were fed a constant diet and were milked twice a day in a herringbone parlor. Milk samples were collected at monthly intervals using a sampling device and then fat, protein, lactose, total solids (TS), and solids-nonfat (SNF) concentrations of raw camel milk were determined with an automatic milk analyzer. For each milk sample, production parameters were recorded and quantities (grams) of milk constituents were calculated. The overall mean quantity and fat, protein, lactose, SNF, and TS concentrations of the morning milk were 4.0 kg, 2.58%, 2.95%, 4.19%, 8.08%, and 10.46%, respectively. Milk quantity showed a positive correlation with lactose and a negative correlation with all other components. Parity exerted a strong effect on all milk parameters. Primiparous dromedaries (n = 60) produced less milk with higher concentrations of components than did multiparous animals (n = 1,468). Milk composition varied among the 7 breeds tested, but none of the genotypes was found to be superior to the others in this respect. We detected a significant, yet small calf sex-biased difference in milk yield and composition. Stage of lactation and season strongly influenced milk yield and all milk components. We also found a significant interaction between month postpartum (mPP) and month of the year. The concentration of all milk components decreased from 1 to 5 mPP. Later, lactose concentration and quantity continued to decrease parallel with decreasing milk production. The concentration of other components showed a temporary increase in mid lactation, from 6 to 11 mPP, and in late lactation, from 18 to 23 mPP. Mean fat, protein, SNF, and TS concentrations showed a high seasonal variation (9.5 to 28.7%), with the lowest and highest values being measured during summer and winter, respectively. This seasonal variation was independent of nutrition and may reflect an endogenous circannual rhythm. We observed a noticeable variation among years. Dromedary camels could provide a useful in vivo model to study the homeorhetic regulation of mammary cell function by endogenous and environmental factors.     

Effect of housing conditions on production,carcass and meat quality traits of growing rabbits

Production, carcass traits and meat quality of rabbits housed in cages or in different pens were compared. Rabbits (n = 579) were sorted into 5 groups: C = cage (2 rabbits/cage); pen without platform: P11 = 9 rabbits/pen; P16 = 14 rabbits/pen; pen with platform: PW = wire net platform, 14 rabbits/pen; PD = platform with straw-litter, 14 rabbits/pen. Feed intake and average daily gain between 5 and 11 weeks, and body weight at 11 weeks were significantly higher in C rabbits than that of the mean of pen-housed groups, while the PD group had the lowest growth performance. C rabbits had the smallest hind part to reference carcass (P < 0.001) and the largest percentage of perirenal and scapular fat (P < 0.001). The meat/bone ratio was the largest in group C (P < 0.05). Differences were recorded in a* value and lipid content of m. Longissimus dorsi. Rabbits housed in cages generally had the best performance whereas those housed in pens with platform exhibited the worst.     

Ventilation rates in schools

Research shows that poor indoor air quality (IAQ) in school buildings can cause a reduction in the students’ performance assessed by short-term computer-based tests; whereas good air quality in classrooms can enhance children's concentration and also teachers’ productivity. Investigation of air quality in classrooms helps us to characterise pollutant levels and implement corrective measures. Outdoor pollution, ventilation equipment, furnishings, and human activities affect IAQ. In school classrooms, the occupancy density is high (1.8–2.4 m²/person) compared to offices (10 m²/person). Ventilation systems expend energy and there is a trend to save energy by reducing ventilation rates. We need to establish the minimum acceptable level of fresh air required for the health of the occupants. This paper describes a project, which will aim to investigate the effect of IAQ and ventilation rates on pupils’ performance and health using psychological tests. The aim is to recommend suitable ventilation rates for classrooms and examine the suitability of the air quality guidelines for classrooms. The air quality, ventilation rates and pupils’ performance in classrooms will be evaluated in parallel measurements. In addition, Visual Analogue Scales will be used to assess subjective perception of the classroom environment and SBS symptoms. Pupil performance will be measured with Computerised Assessment Tests (CAT), and Pen and Paper Performance Tasks while physical parameters of the classroom environment will be recorded using an advanced data logging system. A total number of 20 primary schools in the Reading area are expected to participate in the present investigation, and the pupils participating in this study will be within the age group of 9–11 years. On completion of the project, based on the overall data recommendations for suitable ventilation rates for schools will be formulated.     

Redox-catalytic correlations in oxidised copper-ceria CO-PROX catalysts

Four nanostructured oxidised copper-cerium catalysts prepared by two different methods (impregnation of ceria and coprecipitation of the two components within reverse microemulsions) with varying copper loadings have been examined with the aim of establishing correlations between redox and catalytic properties for preferential oxidation of CO in H₂-rich streams. The analysis is based on ex situ TPR examination both with H₂ or CO as well as operando spectroscopic exploration by DRIFTS and XANES, additionally complemented by conventional catalytic tests. The results reveal redox promoting effects on copper oxide reduction and allow establishing a model of the catalytic behaviour of this type of catalysts which can provide keys to control their CO-PROX catalytic properties.     

Evaluation of the homogenization properties of masterbatches

Appearance is a very important property for many different products, therefore it is important to investigate what types of parameters and processing conditions influence their appearance. The proper investigation of this property requires a reliable and repeatable measurement method. Recently, a novel evaluation method has been developed to evaluate the colour inhomogeneity of injection molded specimens. In this study, this novel inhomogeneity evaluation method was used to compare the homogenization properties of different masterbatches. It was shown using this technique that the homogenization properties of different masterbatch recipes can be evaluated and developed. The results of this method were validated by a group of trained technicians and their results were correlated with the inhomogeneity levels derived from the new method.     

Structure of Pt–Co/Al2O3 and Pt–Co/NaY Bimetallic Catalysts: Characterization by In Situ EXAFS,TPR, XPS and by Activity in Co (Carbon Monoxide) Hydrogenation

Temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and in situ extended X-ray absorption fine structure (EXAFS) studies were performed to investigate Pt-Co/NaY and Pt-Co/Al₂O₃ bimetallic catalysts. The EXAFS experiments were carried out at the Pt L_III and Co K edges of the same sample. This particular approach allows a precise determination of the electronic and structural characteristics of the metallic part of the catalyst. For both systems in situ reduction under pure H₂ results in the formation of nanometer-scale metallic clusters. For both Co and Pt, nearest neighbors are Co atoms. The complete set of parameters implies the presence of two families of nanometer-scale metallic clusters: monometallic Co nanosized particles and Pt-Co bimetallic clusters, in which only Pt-Co bonds exist (no Pt-Pt bonds). TPR and XPS results indicating a reduction of Co²⁺ ions in Pt-Co/NaY to a greater extent than in Pt-Co/Al₂O₃ give evidence of a facilitated reduction. XRD also shows the presence of nanometer-scale particles with only a very small fraction of larger bimetallic particles. In subsequent mild oxidation of the reduced systems the Co nanoparticles are still present inside the supercage of NaY zeolite in bimetallic form and the oxidation of the metallic particles is slowed down. Catalytic behavior is in good agreement with the structure of the Pt-Co bimetallic system.     

Risk sensitive identification of linear stochastic systems

Risk-sensitive identification of AR-processes was first considered in [12]. The purpose of this paper is to extend this original approach to ARMA-processes and even to multi-variable linear stochastic systems. We provide a new definition of a risk-sensitive identification criterion. For this we first consider a recursive identification procedure which is parameterized by a weight-matrix K acting on the stochastic gradient. Using the asymptotic theory of recursive estimation a suitably scaled version of the error process will be approximated by a stationary Gaussian process, see Chapter 4.5, Part II of [1]. The new risk sensitive criterion will be defined in terms of this associated stationary Gaussian process in a familiar manner via an exponential-quadratic cost. The main result of the paper is the minimization of the proposed new criterion with respect to the weight-matrix K over a feasible set E_K, see (22), where the cost function is known to be finite, Theorem 6.1. This results will then be extended to the case when minimization over a feasible set E°_K is considered, see (26), on the complement of which the cost function is known to be infinite, Theorem 6.1. The starting point of our analysis is an expression of the cost function given in LEQG-theory, in particular a result of [10]. A new expression for the cost function will be also given, using stochastic realization theory, as the mutual information rate between two stochastic processes.This research was supported in part by grants from the Swedish Research Council for Engineering Sciences (TFR), the Göran Gustafsson Foundation, the National Research Foundation of Hungary (OTKA) under Grants T015668, T16665, T020984 and T032932.